The present invention relates to electric plugs and more particularly, to a plug for the transmission of high frequency/telecommunication signals, which uses a holding down block to hold down the cable and a cable organizer to divide the twisted pairs of the cable, reducing crosstalk noises.
U.S. Pat. No. 7,018,241B2 discloses a modular cable termination plug having a conductor divider having an entrant barb and a plurality of divider channels, a load bar having a plurality of through holes and a plurality of slots, a plurality of contact terminals, a housing, a strain relief collar, and a strain relief boot. The conductor divider and the load bar allow insertion and alignment of the conductors of the cable and reduce crosstalk noises. However, this plug design uses a great number of component parts that require much labor and time to assemble. Further, the molding or manufacturing cost of every component part of this design of plug is high. A minor error in any step during the assembly process of the plug results in a defective product.
US 2003/0224666A1 teaches the use of a distributor to divide the 8 conductors of the cable. However, because the distributor is directly fastened to the housing, it is difficult to align the conductors, and an error may occur easily when inserting the metal contacts into the plug to touch the conductors.
U.S. Pat. No. 6,238,235B1 teaches the use of a cable organizer to reduce crosstalk noises and the use of a load bar to align the conductors. However, this design does not allow quickly alignment of the 8 conductors of the cable in the load bar. Further, two bracket means must be used so that the load bar and the cable organizer can be inserted into the housing. After insertion of the load bar with the cable organizer into the housing, a position error of the load bar in longitudinal direction relative to the metal contact insertion position at the top side of the housing may occur easily, thereby resulting in a contact error or defective product.
US 2005/0106929A1 discloses a wire aligner that divides the 8 conductors of the cable and keeps the conductor aligned. However, because the conductors are curved when separated, i.e., the front ends of the conductors of the cable are not well organized. After installation of the wire aligner in the housing, the metal contacts may be unable to touch the conductors accurately, thereby resulting in a defective product. Further, the wire aligner may vibrate after assembled with the strain relief member.
FIG. 1 is a schematic view, partially in section, of a modular plug 6 according to the prior art before stamp of the holding down block 612 of the housing 61. FIG. 2 is a cross sectional view of FIG. 1. As illustrated, the pitch among the twisted pairs 74,75; 73,76; 71,72; 77,78 does not change. However, when the holding down block 612 of the housing 61 is stamped against the cable 7, as shown in FIGS. 3 and 4, the bottom side 6121 of the holding down block 612 is pressed on the cable 7, causing deformation of the cable 7. At this time, the pitch among the twisted pairs 74,75; 73,76; 71,72; 77,78 is changed, affecting normal signal transmission.
The present invention has been accomplished under the circumstances in view. According to one aspect of the present invention, the plug comprises a housing, a cable organizer mounted in the housing to divide the twisted pairs of the cable, and a load bar mounted in the housing and connected to the front side of the cable organizer to accommodate the conductors of the twisted pairs of the cable individually. The housing has a holding down block suspending in a top locating slot. The holding down block is stamped into the desired shape to hold down the cable after insertion of the cable with the cable organizer and the load bar, preventing change of the pitch of the twisted pairs of the cable.
According to another aspect of the present invention, the cable organizer has a longitudinally extending top guide groove for receiving the fourth and fifth conductor of the cable, a longitudinally extending bottom guide groove for receiving the third and sixth conductors of the cable, a longitudinally extending left guide groove for receiving the seventh and eighth conductors of the cable, a longitudinally extending right guide groove for receiving the first and second conductors of the cable, a horizontal partition wall that divides the top guide groove and the bottom guide groove and has two extension portions respectively extended from two opposite lateral sides thereof to divide the left guide groove and the right guide groove from the top guide groove and the bottom guide groove.
According to still another aspect of the present invention, the cable organizer has two guide flanges respectively protruded from a front wall thereof around the left guide groove and the right guide groove for engaging into the guide grooves in the rear open chamber of the load bar so that the cable can conveniently and quickly be inserted with the cable organizer and the load bar into the housing for enabling the hold down block of the housing to be driven into the engagement position to hold down the cable so as to complete the installation.
According 6to still another aspect of the present invention, the rear open chamber of the load bar is a tapered chamber, having a top side, a bottom side opposite to the top side, and 8 wire grooves sloping in one direction on each of top and bottom sides in communication with the wire slots of the load bar for guiding the conductors of the cable into the wire slots of the load bar respectively